Curing of thick carbon fiber reinforced thermosetting composite laminates has been a major challenge due to the undesired through-thickness temperature gradient. In this paper, a novel layered self-resistance electric heating (L-SRE) method to cure thick laminates was proposed. The thick laminate was divided into multiple independent sub-layers, and the temperature of each sub-layer was controlled individually. The experiment's results revealed that L-SRE was able to achieve highly homogeneous temperature distribution filed throughthickness both in rapid heating and exothermic reaction stages. The maximum temperature difference of dwell stage for L-SRE process was less than 4.0 C, and the L-SRE process that had an optimized thickness of each sub-layer achieved the minimum mean temperature deviation of 2.1 C, which was 88.46% lower than that of the oven process. By using the optimized L-SRE method, the maximum value of crosslink thermal overshoot was 12.2 C (32.5 C for oven curing). Different layered temperature control strategies were explored, and the lowest energy consumption of 309.7 Wh (19.82% of oven process) was achieved by using the single-power pulsed heating. The method proposed in this paper provided a new solution for high-quality and energy-efficient curing of thick laminates.
The Self-Resistance Electrical (SRE) heating method to cure carbon fiber reinforced polymer (CFRP) part possesses the advantages of rapid and volumetric heating, low energy consumption, and low asset investment. But the current SRE heating methods are difficult to uniformly cure the shaped CFRP parts due to the non-uniformly distributed Joule heat power in the parts with a varying cross-sectional area. In this paper, an optimized multi-zone SRE heating method is proposed, in which the uniform heating and curing process of the shaped CFRP part is firstly achieved. By optimizing the orientation of the rectangular zones, the local overheating caused by the voltage gradient and current diffusion between different zones is notably suppressed. Combined with the electro-thermal numerical analysis, the influence of the positional offset of electrodes in two adjacent zones on the temperature uniformity is investigated. Based on this, an automated zoning algorithm and the prioritizing method of the zone orientation are established. The proposed method is numerically and experimentally validated with the typical shaped CFRP parts, and the results are compared with that of the existing SRE heating method. The proposed method realizes that the maximum in-plane temperature difference of shaped CFRP parts is reduced by more than 80%. This method significantly improves the temperature uniformity of shaped CFRP parts during the multi-zone SRE heating process, which provides a potential solution for high-quality and efficient curing of CFRP parts.
Manipulation of heat distribution in the material is a long-term goal that has been pursued in the field of thermal functional materials. Various thermal manipulation methods have been successfully developed, some of which have realized gorgeous thermal patterns. However, existing thermal functional materials are either difficult to avoid introducing massive external heaters and cables or it is hard to achieve dynamic thermal manipulation with a high thermal resolution and accuracy. In addition, the complicated manufacturing process also limits the wide application of thermal functional materials. Herein, a computed thermal patterning method is proposed, which can dynamically achieve a freewheeling thermal manipulation in the highly versatile and easily manufactured multi-layered material. This method first introduces the principle of tomography into the thermal manipulation by treating heat beams as light energy via a multi-angled rhythmical superposition, enabling the human characters to be written, paintings to be drawn, movies to be played, without embedding any external heaters or cables. A particular thermal diffusion problem in the tomographic process is solved by developing an inverse thermal diffusion optimization. Experimental cases demonstrate the great potential of this method in multi-zoned thermal forming, encrypted messaging, 3D thermal printing, and morphing.
Fibre Reinforced Polymers (FRP) have been widely applied in various industries due to their outstanding properties. As a promising curing technology for FRP parts, the self-resistance electric (SRE) heating method has attracted plenty of attention. However, it is difficult for the SRE heating method to uniformly cure the FRP parts with irregular structures. In this paper, a multi-zoned SRE heating method is proposed, in which the FRP part is divided into several heating zones and the temperature of each zone is regulated independently. A multi-channel electrical voltage control system is developed to realise the multi-zoned SRE heating of a wing-shaped FRP part, in which a rapid zone-based temperature control responsiveness is achieved, and the maximum temperature difference is reduced from 60 °C to less than 10 °C, reaching 2.5 °C at its best. This work presents an alternative for the high efficiency and energy-saving curing process of FRP parts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.